Internal-combustion engine



y 1929. F. B. BROWN" 1 1.119.752

INTERNAL COMBUSTION ENGINE Filed March 9, 1927 Fly 2 Fig. 1

Patented July 2, 1929.

UNITED STATES FREDERICK BERNARD BROWN, OF CHESTER, ENGLAND.

INTERNAL-COMBUSTION ENGINE.

Application filed March 9, 1927, Serial No.

This invention relates to internal combustion engines of the kindcomprising a cylinder (hereinafter referred to as the main cylinder)having slidable therein a sleeve, or sleeves, within which sleeve, orwithin the inner sleeve of which the piston of the engine reciprocatesand also having a movable head, constituted by longitudinally sli-dableplunger which acts, at the proper time, in conjunction with the pistonof the engine to effect the discharge of spent, or inert gases,remaining from the ignition and combustion of previous charges, and thisinvention has for its object to provide an improved engine of theaforesaid kind which is more efficient in operation and in which thesaid spent, or inert gases, are practically wholly discharged.

According to this invention, the head of the main cylinder of the engineis constituted by an auxiliary cylinder of smaller diameter than that ofthe said main cylinder. 7 The auxiliary cylinder may have a part whichextends within the main cylinder of such external diameter that a spaceis provided between the exterior of the said part and the interior ofthe said main cylinder for the accommodation of the valve sleeve, orsleeves, of the engine. Reciprocal within the said auxiliary cylinder isa plunger which is moved outwards when the compression space is to beleft free for the compression of a charge and moved inwards when thesaid compression space is to be occupied by the said plunger whenexhaust is taking place, these movements being effected positively inboth directions preferably by a crank driven from the engine shaft athalf engine speed. The charge of explosive mixture in the compressionspace is ignited by a sparking plug which communicates with theauxiliary cylinder at any suitable part thereof.

I will more particularly describe my invention with reference to theaccompanying drawing in which Figures 1 and. 2 shew, in sections, atright angles to each other, so much of a four cylinder engine as isnecessary to illustrate the invention and also to shew the relativepositions of the main and auxiliary pistons of the engine at each. cycleof operation. In the following description reference is made only to oneof the four cylinders shewn in the drawing.

Referring to the figures, 1 indicates the main cylinder of the enginewhich is shewn surrounded by a water-jacket 2; 3 and 4 two concentricvalve sleeves, slidable within the 173,971, and in Great Britain March9, 1926.

said main cylinder, having inlet and exhaust ports 5 and 6 whichcommunicate, at the proper times, with inlet and exhaust ports 7 and 8,respectively, in the wall of the said main cylinder, 9 the pistonreciprocal in the said sleeve 4 and 10 the piston rod connected to themain crank shaft of the engine, all of which is adapted to operate inthe known manner, The head 11 of the main cylinder 1 is shewn as havingintegral therewith a waterjacketed auxiliary cylinder 11 of lessdiameter than that of the main cylinder 1 and as having a part 11 whichextends within the said main cylinder, the external diameter of the saidextension being such that a space 12 is provided between it and the wallof the said main cylinder for the accommodation. of the valve sleeves 3and 4.

V The extension 11 of the head 11 may be provided with a ring, or rings,such for example as shewn at 11 to ensure a gas-tight joint between thesaid extension and the in- "ner sleeve 4. Reciprocal within theauxiliary cylinder 11 is a plunger 13 which is moved outwards when thecompression space 14 is to be left free for the compression of a chargeof explosive mixture and moved inwards when the said compression spaceis to be occupied by the said plunger when exhaust is taking place. Anysuitable means may be provided for positively effecting the movements ofthe plunger 13 at the proper times, for example, the said movements maybe effected by a crank 15 driven from the engine shaft at half enginespeed.

The charge of explosive mixture in the compression space 14 is ignitedby a sparking plug 16 secured in a passage or channel, 17 incommunication with the interior of the auxiliary cylinder 11constituting the said compression space.

In the arrangement shewn as each piston 9 descends for the suctionstroke the inlet port 7 is opened and the explosive charge drawn inuntil the said piston is at, or towards, the lower end of the innersleeve 4 when the said port is closed, the plunger 13 being then towardsthe bottom of the auxiliary cylinder 11 as shewn at A Figure 1. Thepiston. 9 and the plunger 13 then ascend in their respective cylinders,the said piston forcing the explosive mixture out of the inner sleeve 4into the auxiliary cylinder 11 where it is compressed in the compressionspace 14. At the end of this compression stroke the piston 9 is at, ortowards theupper end of the inner sleeve 4 and theplunger 13 is at, ortowards, the upper end of the auxiliary cylinder 11 as shewn at BFigure 1. Firing of the explosive mixture is then eflected and at theend of the firing, or working, stroke the plunger 13 would still betowards the upper end of its cylinder 11 when the piston 9 is at, ortowards, the lower end of the inner sleeve 4, as shewn at'C, Figure 1.At the next stroke of the engine the piston 9 and the plunger 13 advancetowards each other and force the products of combustion through the nowopen exhaust port 8. At the end of this exhaust stroke the piston 9 willbe at the upper end of the inner sleeve 4 and the plunger 13 at thelower end of its cylinder 11 as shewn at D Figure 1, there then beingsuch space, shewn at 14:, between the upper surface of the piston 9 andthe under surfaces of the head of the cylinder 11 and the plunger 13,sufficient only to allow for the necessary working clearance betweenthem.

It is to be understood that the invention is not limited to the precisedetails of construction, or arrangement, of the parts hereinbeforedescribed and shewn as it is obvious that modifications may bemade'without departing from the scope of the invention, for example, theauxiliary cylinder instead of being made integral with the head 11 maybe constituted by a sleeve, or liner, suitably secured in the said headof the main cylinder of the engine, and also, it will be understood thatthe invention is applicablet'or use in engines'having any desired numberof cylinders.

What I claim is v, 1. In an internal combustion engine a main cylinderhaving movable therein a. valve sleeve, within which sleeve the pistonof the engine reciproeates, the said sleeve being provided with inletand exhaust ports which control inlet and exhaust passages in the saidcylinder, in combination with an auxiliary cylinder in the head of themain cylinder, said auxiliary cylinder having a part which ex- A tendswithin the said main cylinder, and is of such external diameter that aspace is provided between the exterior of the said part and the interiorof the said main cylinder for the accommodation of the valve sleeve ofthe engine, and an auxiliary piston reciprocable within said auxiliarycylinder for varying the combustion space, substantially as described.

2. In an internal combustion engine of the kind referred to having inthe head of the main cylinder of the engine an auxiliary cylinder with apart which extends within the said main cylinder the said part having awater-j acket within the main cylinder, and an auxiliary pistonreciprocahle within said auxiliary cylinder for varying the combustionspace.

3. In an internal combustion engine of the kind referred to having inthe head oi the main cylinder of the engine an auxiliary cylinder with apart which extends within the said main cylinder, said auxiliarycylinder constituting the explosion chamber, and ha ving a sparking plugsecured in a passage, or channel, in con'nnunication with the interiorof the said auxiliary cylinder, and an anxiliary piston reciprocablewithin said auxiliary cylinder for varying the combustion space.

In testimony whereof I have signed my name to this specification.

FREDERICK BERNARD BRO VN.

